A. SET CONCEPT

1. UNDERSTANDING
An understanding of the set is one of the important and fundamental concepts in modern mathematics. The concept of the set was first introduced officially by a German mathematician Georg Cantor in the 19th century.

The concept of the set is found, explicitly or implicitly, in every field of pure and applied mathematics. Explicitly, the principles and terminology set used to make the statement more clear and precise mathematics and to explain concepts such as limited and unlimited.

What is the set?

SET is a collection of objects or anything else that is clearly defined so that we can easily find out whether an object or something else was included in a set or not.

The objects or other things that are included in a set called members or elements of the set or collection of these.
If someone says: "Above the dining table is a stack of notebooks." So we can imagine that on the dining table was a stack of notebooks, in the pile notebook only, not other objects, papers or other.

In a sentence on a stack is a set and a member or set of elements that are writing books, writing books and not just reading books or other objects.
In the set of the above a member conditions are notebooks are piled on the dining table, and from the membership requirement is to clearly know where the objects belonging to members of the set which do not include members of the set.

So it is clear to create a Set, the membership requirements of the members or elements of a set that will be formed must be presented clearly so that for any set anyone can tell whether an object or certain other things that are members of the set or not.

Terms or the nature of the set of member characteristics on a set. Characteristic is what distinguishes a set with another set. These characteristics are also useful for giving a name to a set.

Another example:
The set of integers. Here the member characteristics / requirements of a set are integers.
Association of European countries. Here the member requirements / characteristics are the countries in continental Europe
Etc..